release: 0.1.0

Renamed `Container.contents` to `Container.content` to be in line with
the corresponding `Element` function name. This has also been done for
the properties structs used by the `Container`.

build.zig.zon

@@ -24,11 +24,11 @@
 
     // This is a [Semantic Version](https://semver.org/).
     // In a future version of Zig it will be used for package deduplication.
-    .version = "0.0.0",
+    .version = "0.1.0",
 
     // Tracks the earliest Zig version that the package considers to be a
     // supported use case.
-    .minimum_zig_version = "0.14.0-dev.3445+6c3cbb0c8",
+    .minimum_zig_version = "0.15.0-dev.56+d0911786c",
 
     // This field is optional.
     // Each dependency must either provide a `url` and `hash`, or a `path`.
@@ -42,11 +42,9 @@
         },
     },
     .paths = .{
+        "LICENSE",
         "build.zig",
         "build.zig.zon",
         "src",
-        // For example...
-        //"LICENSE",
-        //"README.md",
     },
 }

examples/demo.zig

@@ -13,10 +13,9 @@ const QuitText = struct {
         return .{ .ptr = this, .vtable = &.{ .content = content } };
     }
 
-    pub fn content(ctx: *anyopaque, cells: []zterm.Cell, origin: zterm.Point, size: zterm.Point) !void {
+    pub fn content(ctx: *anyopaque, cells: []zterm.Cell, size: zterm.Point) !void {
         _ = ctx;
         std.debug.assert(cells.len == @as(usize, size.x) * @as(usize, size.y));
-        _ = origin;
 
         const y = 2;
         const x = size.x / 2 -| (text.len / 2);
@@ -151,7 +150,8 @@ pub fn main() !void {
         }
 
         try renderer.resize();
-        container.resize(.{}, renderer.size);
+        container.resize(renderer.size);
+        container.reposition(.{});
         try renderer.render(@TypeOf(container), &container);
         try renderer.flush();
     }

examples/elements/button.zig

@@ -14,10 +14,9 @@ const QuitText = struct {
         return .{ .ptr = this, .vtable = &.{ .content = content } };
     }
 
-    fn content(ctx: *anyopaque, cells: []zterm.Cell, origin: zterm.Point, size: zterm.Point) !void {
+    fn content(ctx: *anyopaque, cells: []zterm.Cell, size: zterm.Point) !void {
         _ = ctx;
         std.debug.assert(cells.len == @as(usize, size.x) * @as(usize, size.y));
-        _ = origin;
 
         const row = 2;
         const col = size.x / 2 -| (text.len / 2);
@@ -65,10 +64,9 @@ const Clickable = struct {
         }
     }
 
-    fn content(ctx: *anyopaque, cells: []zterm.Cell, origin: zterm.Point, size: zterm.Point) !void {
+    fn content(ctx: *anyopaque, cells: []zterm.Cell, size: zterm.Point) !void {
         const this: *@This() = @ptrCast(@alignCast(ctx));
         std.debug.assert(cells.len == @as(usize, size.x) * @as(usize, size.y));
-        _ = origin;
 
         const row = size.y / 2 -| (text.len / 2);
         const col = size.x / 2 -| (text.len / 2);
@@ -142,7 +140,8 @@ pub fn main() !void {
         }
 
         try renderer.resize();
-        container.resize(.{}, renderer.size);
+        container.resize(renderer.size);
+        container.reposition(.{});
         try renderer.render(@TypeOf(container), &container);
         try renderer.flush();
     }

examples/elements/input.zig

@@ -14,10 +14,9 @@ const QuitText = struct {
         return .{ .ptr = this, .vtable = &.{ .content = content } };
     }
 
-    fn content(ctx: *anyopaque, cells: []zterm.Cell, origin: zterm.Point, size: zterm.Point) !void {
+    fn content(ctx: *anyopaque, cells: []zterm.Cell, size: zterm.Point) !void {
         _ = ctx;
         std.debug.assert(cells.len == @as(usize, size.x) * @as(usize, size.y));
-        _ = origin;
 
         const row = 2;
         const col = size.x / 2 -| (text.len / 2);
@@ -75,10 +74,9 @@ const InputField = struct {
         }
     }
 
-    fn content(ctx: *anyopaque, cells: []zterm.Cell, origin: zterm.Point, size: zterm.Point) !void {
+    fn content(ctx: *anyopaque, cells: []zterm.Cell, size: zterm.Point) !void {
         const this: *@This() = @ptrCast(@alignCast(ctx));
         std.debug.assert(cells.len == @as(usize, size.x) * @as(usize, size.y));
-        _ = origin;
 
         if (this.input.items.len == 0) return;
 
@@ -156,7 +154,8 @@ pub fn main() !void {
         }
 
         try renderer.resize();
-        container.resize(.{}, renderer.size);
+        container.resize(renderer.size);
+        container.reposition(.{});
         try renderer.render(@TypeOf(container), &container);
         try renderer.flush();
     }

examples/elements/scrollable.zig

@@ -13,10 +13,9 @@ const QuitText = struct {
         return .{ .ptr = this, .vtable = &.{ .content = content } };
     }
 
-    fn content(ctx: *anyopaque, cells: []zterm.Cell, origin: zterm.Point, size: zterm.Point) !void {
+    fn content(ctx: *anyopaque, cells: []zterm.Cell, size: zterm.Point) !void {
         _ = ctx;
         std.debug.assert(cells.len == @as(usize, size.x) * @as(usize, size.y));
-        _ = origin;
 
         const row = 2;
         const col = size.x / 2 -| (text.len / 2);
@@ -43,10 +42,9 @@ const HelloWorldText = packed struct {
         };
     }
 
-    fn content(ctx: *anyopaque, cells: []zterm.Cell, origin: zterm.Point, size: zterm.Point) !void {
+    fn content(ctx: *anyopaque, cells: []zterm.Cell, size: zterm.Point) !void {
         _ = ctx;
         std.debug.assert(cells.len == @as(usize, size.x) * @as(usize, size.y));
-        _ = origin;
 
         const row = size.y / 2;
         const col = size.x / 2 -| (text.len / 2);
@@ -193,7 +191,8 @@ pub fn main() !void {
         }
 
         try renderer.resize();
-        container.resize(.{}, renderer.size);
+        container.resize(renderer.size);
+        container.reposition(.{});
         try renderer.render(@TypeOf(container), &container);
         try renderer.flush();
     }

examples/errors.zig

@@ -12,10 +12,9 @@ const QuitText = struct {
         return .{ .ptr = this, .vtable = &.{ .content = content } };
     }
 
-    fn content(ctx: *anyopaque, cells: []zterm.Cell, origin: zterm.Point, size: zterm.Point) !void {
+    fn content(ctx: *anyopaque, cells: []zterm.Cell, size: zterm.Point) !void {
         _ = ctx;
         std.debug.assert(cells.len == @as(usize, size.x) * @as(usize, size.y));
-        _ = origin;
 
         const row = 2;
         const col = size.x / 2 -| (text.len / 2);
@@ -39,10 +38,9 @@ const InfoText = struct {
         return .{ .ptr = this, .vtable = &.{ .content = content } };
     }
 
-    fn content(ctx: *anyopaque, cells: []zterm.Cell, origin: zterm.Point, size: zterm.Point) !void {
+    fn content(ctx: *anyopaque, cells: []zterm.Cell, size: zterm.Point) !void {
         _ = ctx;
         std.debug.assert(cells.len == @as(usize, size.x) * @as(usize, size.y));
-        _ = origin;
 
         const row = 2;
         const col = size.x / 2 -| (text.len / 2);
@@ -75,10 +73,9 @@ const ErrorNotification = struct {
         }
     }
 
-    fn content(ctx: *anyopaque, cells: []zterm.Cell, origin: zterm.Point, size: zterm.Point) !void {
+    fn content(ctx: *anyopaque, cells: []zterm.Cell, size: zterm.Point) !void {
         const this: *@This() = @ptrCast(@alignCast(ctx));
         std.debug.assert(cells.len == @as(usize, size.x) * @as(usize, size.y));
-        _ = origin;
 
         if (this.msg) |msg| {
             const row = size.y -| 2;
@@ -154,7 +151,8 @@ pub fn main() !void {
         }
 
         try renderer.resize();
-        container.resize(.{}, renderer.size);
+        container.resize(renderer.size);
+        container.reposition(.{});
         try renderer.render(@TypeOf(container), &container);
         try renderer.flush();
     }

examples/layouts/grid.zig

@@ -15,10 +15,9 @@ const QuitText = struct {
         };
     }
 
-    fn content(ctx: *anyopaque, cells: []zterm.Cell, origin: zterm.Point, size: zterm.Point) !void {
+    fn content(ctx: *anyopaque, cells: []zterm.Cell, size: zterm.Point) !void {
         _ = ctx;
         std.debug.assert(cells.len == @as(usize, size.x) * @as(usize, size.y));
-        _ = origin;
 
         const row = 2;
         const col = size.x / 2 -| (text.len / 2);
@@ -108,7 +107,8 @@ pub fn main() !void {
         }
 
         try renderer.resize();
-        container.resize(.{}, renderer.size);
+        container.resize(renderer.size);
+        container.reposition(.{});
         try renderer.render(@TypeOf(container), &container);
         try renderer.flush();
     }

examples/layouts/horizontal.zig

@@ -15,10 +15,9 @@ const QuitText = struct {
         };
     }
 
-    fn content(ctx: *anyopaque, cells: []zterm.Cell, origin: zterm.Point, size: zterm.Point) !void {
+    fn content(ctx: *anyopaque, cells: []zterm.Cell, size: zterm.Point) !void {
         _ = ctx;
         std.debug.assert(cells.len == @as(usize, size.x) * @as(usize, size.y));
-        _ = origin;
 
         const row = 2;
         const col = size.x / 2 -| (text.len / 2);
@@ -100,7 +99,8 @@ pub fn main() !void {
         }
 
         try renderer.resize();
-        container.resize(.{}, renderer.size);
+        container.resize(renderer.size);
+        container.reposition(.{});
         try renderer.render(@TypeOf(container), &container);
         try renderer.flush();
     }

examples/layouts/mixed.zig

@@ -15,10 +15,9 @@ const QuitText = struct {
         };
     }
 
-    fn content(ctx: *anyopaque, cells: []zterm.Cell, origin: zterm.Point, size: zterm.Point) !void {
+    fn content(ctx: *anyopaque, cells: []zterm.Cell, size: zterm.Point) !void {
         _ = ctx;
         std.debug.assert(cells.len == @as(usize, size.x) * @as(usize, size.y));
-        _ = origin;
 
         const row = 2;
         const col = size.x / 2 -| (text.len / 2);
@@ -71,7 +70,12 @@ pub fn main() !void {
                 .rectangle = .{ .fill = .yellow },
             }, .{}));
         } else {
-            try column.append(try App.Container.init(allocator, .{}, .{}));
+            try column.append(try App.Container.init(allocator, .{
+                .size = .{
+                    .dim = .{ .y = 4 },
+                    .grow = .horizontal,
+                },
+            }, .{}));
         }
         try column.append(try App.Container.init(allocator, .{
             .rectangle = .{ .fill = .blue },
@@ -111,7 +115,8 @@ pub fn main() !void {
         }
 
         try renderer.resize();
-        container.resize(.{}, renderer.size);
+        container.resize(renderer.size);
+        container.reposition(.{});
         try renderer.render(@TypeOf(container), &container);
         try renderer.flush();
     }

examples/layouts/vertical.zig

@@ -15,10 +15,9 @@ const QuitText = struct {
         };
     }
 
-    fn content(ctx: *anyopaque, cells: []zterm.Cell, origin: zterm.Point, size: zterm.Point) !void {
+    fn content(ctx: *anyopaque, cells: []zterm.Cell, size: zterm.Point) !void {
         _ = ctx;
         std.debug.assert(cells.len == @as(usize, size.x) * @as(usize, size.y));
-        _ = origin;
 
         const row = 2;
         const col = size.x / 2 -| (text.len / 2);
@@ -99,7 +98,8 @@ pub fn main() !void {
         }
 
         try renderer.resize();
-        container.resize(.{}, renderer.size);
+        container.resize(renderer.size);
+        container.reposition(.{});
         try renderer.render(@TypeOf(container), &container);
         try renderer.flush();
     }

examples/styles/palette.zig

@@ -12,10 +12,9 @@ const QuitText = struct {
         return .{ .ptr = this, .vtable = &.{ .content = content } };
     }
 
-    fn content(ctx: *anyopaque, cells: []zterm.Cell, origin: zterm.Point, size: zterm.Point) !void {
+    fn content(ctx: *anyopaque, cells: []zterm.Cell, size: zterm.Point) !void {
         _ = ctx;
         std.debug.assert(cells.len == @as(usize, size.x) * @as(usize, size.y));
-        _ = origin;
 
         const row = 2;
         const col = size.x / 2 -| (text.len / 2);
@@ -95,7 +94,8 @@ pub fn main() !void {
         }
 
         try renderer.resize();
-        container.resize(.{}, renderer.size);
+        container.resize(renderer.size);
+        container.reposition(.{});
         try renderer.render(@TypeOf(container), &container);
         try renderer.flush();
     }

examples/styles/text.zig

@@ -12,10 +12,9 @@ const QuitText = struct {
         return .{ .ptr = this, .vtable = &.{ .content = content } };
     }
 
-    fn content(ctx: *anyopaque, cells: []zterm.Cell, origin: zterm.Point, size: zterm.Point) !void {
+    fn content(ctx: *anyopaque, cells: []zterm.Cell, size: zterm.Point) !void {
         _ = ctx;
         std.debug.assert(cells.len == @as(usize, size.x) * @as(usize, size.y));
-        _ = origin;
 
         const row = 2;
         const col = size.x / 2 -| (text.len / 2);
@@ -39,11 +38,10 @@ const TextStyles = struct {
         return .{ .ptr = this, .vtable = &.{ .content = content } };
     }
 
-    fn content(ctx: *anyopaque, cells: []zterm.Cell, origin: zterm.Point, size: zterm.Point) !void {
+    fn content(ctx: *anyopaque, cells: []zterm.Cell, size: zterm.Point) !void {
         @setEvalBranchQuota(50000);
         _ = ctx;
         std.debug.assert(cells.len == @as(usize, size.x) * @as(usize, size.y));
-        _ = origin;
 
         var row: usize = 0;
         var col: usize = 0;
@@ -151,7 +149,8 @@ pub fn main() !void {
         }
 
         try renderer.resize();
-        container.resize(.{}, renderer.size);
+        container.resize(renderer.size);
+        container.reposition(.{});
         try renderer.render(@TypeOf(container), &container);
         try renderer.flush();
     }

src/container.zig

@@ -38,7 +38,7 @@ pub const Border = packed struct {
         pub const vertical: @This() = .{ .top = true, .bottom = true };
     } = .{},
 
-    pub fn contents(this: @This(), cells: []Cell, size: Point) void {
+    pub fn content(this: @This(), cells: []Cell, size: Point) void {
         std.debug.assert(cells.len == @as(usize, size.x) * @as(usize, size.y));
 
         const frame = switch (this.corners) {
@@ -154,7 +154,7 @@ pub const Rectangle = packed struct {
     fill: Color = .default,
 
     // NOTE caller owns `Cells` slice and ensures that `cells.len == size.x * size.y`
-    pub fn contents(this: @This(), cells: []Cell, size: Point) void {
+    pub fn content(this: @This(), cells: []Cell, size: Point) void {
         std.debug.assert(cells.len == @as(usize, size.x) * @as(usize, size.y));
 
         for (0..size.y) |row| {
@@ -341,7 +341,7 @@ pub const Layout = packed struct {
         } = .line,
     } = .{},
 
-    pub fn contents(this: @This(), comptime C: type, cells: []Cell, origin: Point, size: Point, children: []const C) void {
+    pub fn content(this: @This(), comptime C: type, cells: []Cell, origin: Point, size: Point, children: []const C) void {
         std.debug.assert(cells.len == @as(usize, size.x) * @as(usize, size.y));
 
         if (this.separator.enabled and children.len > 1) {
@@ -616,7 +616,7 @@ pub fn Container(comptime Event: type) type {
             try this.elements.append(element);
         }
 
-        fn reposition(this: *@This(), origin: Point) void {
+        pub fn reposition(this: *@This(), origin: Point) void {
             const layout = this.properties.layout;
             this.origin = origin;
             this.element.reposition(origin);
@@ -690,10 +690,10 @@ pub fn Container(comptime Event: type) type {
                 .fixed => this.properties.size.dim,
                 .horizontal => .{
                     .x = @max(size.x, this.properties.size.dim.x),
-                    .y = size.y,
+                    .y = this.properties.size.dim.y,
                 },
                 .vertical => .{
-                    .x = size.x,
+                    .x = this.properties.size.dim.x,
                     .y = @max(size.y, this.properties.size.dim.y),
                 },
             };
@@ -701,7 +701,7 @@ pub fn Container(comptime Event: type) type {
             return this.size;
         }
 
-        // growable implicitly requires the root `Container` to have a set a size property to the size of the available terminal screen
+        /// growable implicitly requires the root `Container` to have a set a size property to the size of the available terminal screen
         fn grow_resize(this: *@This(), max_size: Point) void {
             log.debug("grow_size: {any}", .{this.size});
             const layout = this.properties.layout;
@@ -750,18 +750,30 @@ pub fn Container(comptime Event: type) type {
             var growable_children: usize = 0;
             var first_growable_child: *@This() = undefined;
             for (this.elements.items) |*child| {
-                if (child.properties.size.grow != .fixed) {
-                    if (growable_children == 0) first_growable_child = child;
-                    growable_children += 1;
-
-                    switch (layout.direction) {
-                        .horizontal => if (child.properties.size.grow != .vertical) {
-                            child.size.y = available;
-                        },
-                        .vertical => if (child.properties.size.grow != .horizontal) {
-                            child.size.x = available;
-                        },
-                    }
+                // layout direction side growth
+                switch (child.properties.size.grow) {
+                    .fixed => continue,
+                    .both => {
+                        if (growable_children == 0) first_growable_child = child;
+                        growable_children += 1;
+                    },
+                    .horizontal => if (layout.direction == .horizontal) {
+                        if (growable_children == 0) first_growable_child = child;
+                        growable_children += 1;
+                    },
+                    .vertical => if (layout.direction == .vertical) {
+                        if (growable_children == 0) first_growable_child = child;
+                        growable_children += 1;
+                    },
+                }
+                // non layout direction side growth
+                switch (layout.direction) {
+                    .horizontal => if (child.properties.size.grow == .vertical or child.properties.size.grow == .both) {
+                        child.size.y = available;
+                    },
+                    .vertical => if (child.properties.size.grow == .horizontal or child.properties.size.grow == .both) {
+                        child.size.x = available;
+                    },
                 }
             }
 
@@ -833,7 +845,7 @@ pub fn Container(comptime Event: type) type {
             for (this.elements.items) |*child| child.grow_resize(child.size);
         }
 
-        pub fn resize(this: *@This(), origin: Point, size: Point) void {
+        pub fn resize(this: *@This(), size: Point) void {
             // NOTE assume that this function is only called for the root `Container`
             const fit_size = this.fit_resize();
             // if (fit_size.y > size.y or fit_size.x > size.x) @panic("error: cannot render in available space");
@@ -850,7 +862,6 @@ pub fn Container(comptime Event: type) type {
                 },
             }
             this.grow_resize(this.size);
-            this.reposition(origin);
         }
 
         pub fn handle(this: *@This(), event: Event) !void {
@@ -866,17 +877,17 @@ pub fn Container(comptime Event: type) type {
             }
         }
 
-        pub fn contents(this: *const @This()) ![]const Cell {
+        pub fn content(this: *const @This()) ![]const Cell {
             if (this.size.x == 0 or this.size.y == 0) return Error.TooSmall;
             const cells = try this.allocator.alloc(Cell, @as(usize, this.size.x) * @as(usize, this.size.y));
             @memset(cells, .{});
             errdefer this.allocator.free(cells);
 
-            this.properties.layout.contents(@This(), cells, this.origin, this.size, this.elements.items);
-            this.properties.border.contents(cells, this.size);
-            this.properties.rectangle.contents(cells, this.size);
+            this.properties.layout.content(@This(), cells, this.origin, this.size, this.elements.items);
+            this.properties.border.content(cells, this.size);
+            this.properties.rectangle.content(cells, this.size);
 
-            try this.element.content(cells, this.origin, this.size);
+            try this.element.content(cells, this.size);
 
             // DEBUG render corresponding top left corner of this `Container` *red*
             // cells[0].style.fg = .red;
@@ -892,3 +903,51 @@ test {
     _ = Layout;
     _ = Rectangle;
 }
+
+test "Container Fixed and Grow Size Vertical" {
+    const event = @import("event.zig");
+    const testing = @import("testing.zig");
+
+    var container: Container(event.SystemEvent) = try .init(std.testing.allocator, .{
+        .layout = .{ .direction = .vertical },
+    }, .{});
+    try container.append(try .init(std.testing.allocator, .{
+        .size = .{
+            .dim = .{ .y = 5 },
+            .grow = .horizontal,
+        },
+        .rectangle = .{ .fill = .grey },
+    }, .{}));
+    try container.append(try .init(std.testing.allocator, .{
+        .rectangle = .{ .fill = .red },
+    }, .{}));
+    defer container.deinit();
+
+    try testing.expectContainerScreen(.{
+        .y = 20,
+        .x = 30,
+    }, &container, @import("test/container/fixed_grow_vertical.zon"));
+}
+
+test "Container Fixed and Grow Size Horizontal" {
+    const event = @import("event.zig");
+    const testing = @import("testing.zig");
+
+    var container: Container(event.SystemEvent) = try .init(std.testing.allocator, .{}, .{});
+    try container.append(try .init(std.testing.allocator, .{
+        .size = .{
+            .dim = .{ .x = 5 },
+            .grow = .vertical,
+        },
+        .rectangle = .{ .fill = .grey },
+    }, .{}));
+    try container.append(try .init(std.testing.allocator, .{
+        .rectangle = .{ .fill = .red },
+    }, .{}));
+    defer container.deinit();
+
+    try testing.expectContainerScreen(.{
+        .y = 20,
+        .x = 30,
+    }, &container, @import("test/container/fixed_grow_horizontal.zon"));
+}

src/element.zig

@@ -16,7 +16,7 @@ pub fn Element(Event: type) type {
             resize: ?*const fn (ctx: *anyopaque, size: Point) void = null,
             reposition: ?*const fn (ctx: *anyopaque, origin: Point) void = null,
             handle: ?*const fn (ctx: *anyopaque, event: Event) anyerror!void = null,
-            content: ?*const fn (ctx: *anyopaque, cells: []Cell, origin: Point, size: Point) anyerror!void = null,
+            content: ?*const fn (ctx: *anyopaque, cells: []Cell, size: Point) anyerror!void = null,
         };
 
         /// Resize the corresponding `Element` with the given *size*.
@@ -58,9 +58,9 @@ pub fn Element(Event: type) type {
         ///   non-recoverable (i.e. an allocation error, system error, etc.).
         ///   Otherwise user specific errors should be caught using the `handle`
         ///   function before the rendering of the `Container` happens.
-        pub inline fn content(this: @This(), cells: []Cell, origin: Point, size: Point) !void {
+        pub inline fn content(this: @This(), cells: []Cell, size: Point) !void {
             if (this.vtable.content) |content_fn|
-                try content_fn(this.ptr, cells, origin, size);
+                try content_fn(this.ptr, cells, size);
         }
     };
 }
@@ -83,6 +83,7 @@ pub fn Scrollable(Event: type) type {
                 .ptr = this,
                 .vtable = &.{
                     .resize = resize,
+                    .reposition = reposition,
                     .handle = handle,
                     .content = content,
                 },
@@ -94,12 +95,15 @@ pub fn Scrollable(Event: type) type {
             this.size = size;
 
             // TODO scrollbar space - depending on configuration and only if necessary?
-            std.log.debug("----", .{});
-            this.container.resize(.{}, this.size);
-            std.log.debug("----", .{});
+            this.container.resize(this.size);
             this.container_size = this.container.size;
         }
 
+        fn reposition(ctx: *anyopaque, _: Point) void {
+            const this: *@This() = @ptrCast(@alignCast(ctx));
+            this.container.reposition(.{});
+        }
+
         fn handle(ctx: *anyopaque, event: Event) !void {
             const this: *@This() = @ptrCast(@alignCast(ctx));
             switch (event) {
@@ -132,13 +136,13 @@ pub fn Scrollable(Event: type) type {
             }
         }
 
-        fn render_container(container: Container(Event), cells: []Cell, container_origin: Point, container_size: Point) !void {
+        fn render_container(container: Container(Event), cells: []Cell, container_size: Point) !void {
             const size = container.size;
             const origin = container.origin;
-            const contents = try container.contents();
+            const contents = try container.content();
             defer container.allocator.free(contents);
 
-            const anchor = (@as(usize, origin.y -| container_origin.y) * @as(usize, container_size.x)) + @as(usize, origin.x -| container_origin.x);
+            const anchor = (@as(usize, origin.y) * @as(usize, container_size.x)) + @as(usize, origin.x);
 
             var idx: usize = 0;
             blk: for (0..size.y) |row| {
@@ -150,25 +154,23 @@ pub fn Scrollable(Event: type) type {
                 }
             }
 
-            for (container.elements.items) |child| try render_container(child, cells, origin, size);
+            for (container.elements.items) |child| try render_container(child, cells, size);
         }
 
-        fn content(ctx: *anyopaque, cells: []Cell, origin: Point, size: Point) !void {
+        fn content(ctx: *anyopaque, cells: []Cell, size: Point) !void {
             const this: *@This() = @ptrCast(@alignCast(ctx));
-            _ = origin;
             std.debug.assert(cells.len == @as(usize, this.size.x) * @as(usize, this.size.y));
 
             const container_size = this.container.size;
-            const container_origin = this.container.origin;
             const container_cells = try this.container.allocator.alloc(Cell, @as(usize, container_size.x) * @as(usize, container_size.y));
             {
-                const container_cells_const = try this.container.contents();
+                const container_cells_const = try this.container.content();
                 defer this.container.allocator.free(container_cells_const);
                 std.debug.assert(container_cells_const.len == @as(usize, container_size.x) * @as(usize, container_size.y));
                 @memcpy(container_cells, container_cells_const);
             }
 
-            for (this.container.elements.items) |child| try render_container(child, container_cells, container_origin, container_size);
+            for (this.container.elements.items) |child| try render_container(child, container_cells, container_size);
 
             const anchor = (@as(usize, this.anchor.y) * @as(usize, container_size.x)) + @as(usize, this.anchor.x);
             // TODO render scrollbar according to configuration!
@@ -233,7 +235,8 @@ test "scrollable vertical" {
     var renderer: testing.Renderer = .init(allocator, size);
     defer renderer.deinit();
 
-    container.resize(.{}, size);
+    container.resize(size);
+    container.reposition(.{});
     try renderer.render(Container(event.SystemEvent), &container);
     try testing.expectEqualCells(.{}, renderer.size, @import("test/element/scrollable.vertical.top.zon"), renderer.screen);
 
@@ -310,7 +313,8 @@ test "scrollable horizontal" {
     var renderer: testing.Renderer = .init(allocator, size);
     defer renderer.deinit();
 
-    container.resize(.{}, size);
+    container.resize(size);
+    container.reposition(.{});
     try renderer.render(Container(event.SystemEvent), &container);
     try testing.expectEqualCells(.{}, renderer.size, @import("test/element/scrollable.horizontal.left.zon"), renderer.screen);
 

src/render.zig

@@ -64,7 +64,7 @@ pub const Buffered = struct {
     pub fn render(this: *@This(), comptime T: type, container: *T) !void {
         const size: Point = container.size;
         const origin: Point = container.origin;
-        const cells: []const Cell = try container.contents();
+        const cells: []const Cell = try container.content();
 
         if (cells.len == 0) return;
 

src/testing.zig

@@ -48,7 +48,7 @@ pub const Renderer = struct {
     pub fn render(this: *@This(), comptime T: type, container: *const T) !void {
         const size: Point = container.size;
         const origin: Point = container.origin;
-        const cells: []const Cell = try container.contents();
+        const cells: []const Cell = try container.content();
 
         if (cells.len == 0) return;
 
@@ -121,7 +121,8 @@ pub fn expectContainerScreen(size: Point, container: *Container(event.SystemEven
     defer renderer.deinit();
 
     try renderer.resize(size);
-    container.resize(.{}, size);
+    container.resize(size);
+    container.reposition(.{});
     try renderer.render(Container(event.SystemEvent), container);
 
     try expectEqualCells(.{}, renderer.size, expected, renderer.screen);